The present disclosure relates to stators for rotating electrical machines.
A stator described in Japanese Patent Application Publication No. JP 2007-97262 (JP 2007-97262 A) is known as a stator for a rotating electrical machine. JP 2007-97262 A discloses a technique that improves flexibility in arrangement of coil-to-coil jumper wires (300) each connecting an inner coil (100) and an outer coil (200) in series in the configuration including inner coils (100) disposed in the inner parts in the radial direction of slots and outer coils (200) disposed in the outer parts in the radial direction of the slots. Specifically, each head jumper portion (305) that connects two tilted jumper portions (303, 304) in the coil-to-coil jumper wire (300) includes a direction changing portion that reverses the direction in which the head jumper portion (305) extends in the circumferential direction, whereby the two tilted jumper portions (303, 304) can be made to be tilted in the same direction in the circumferential direction. JP 2007-97262 A describes that such a configuration allows the coil-to-coil jumper wires (300) to be disposed at positions where conventional coil-to-coil jumper wires cannot be disposed.
For example, there is a case where not only such coil-to-coil jumper wires (300) but also a neutral terminal forming a neutral point and a power line terminal connecting to a power supply are disposed at an axial outer end of a coil end portion. A plurality of jumper portions (jumper wires) corresponding to at least the number of coil phases are connected to the neutral terminal. In the case where a single phase coil includes a plurality of coil portions connected in parallel with each other, in the case where a plurality of liner conductors are wound in bundles in a core, etc., the plurality of jumper portions may also be connected to the power line terminal. In the case where such a plurality of jumper portions are connected at the neutral terminal or the power line terminal by crimping etc., the plurality of jumper portions are usually required to extend in the same direction. One method to make the plurality of jumper portions extend in the same direction is to form in the jumper portion folded-back portions that reverse the direction in which the jumper portion extends, like, e.g., the direction changing portions of the coil-to-coil jumper wires (300) described in JP 2007-97262 A. In this case, however, since space for folding back is required, the neutral terminal or the power line terminal need to be disposed away from the coil end portion in the axial direction, whereby size in the axial direction of the stator may be increased accordingly.